Water from alternative sources such as rainwater tanks and boreholes can be used for for toilet flushing and washing, but what about drinking and cooking? WWF informs us on how to ensure that we enjoy safe drinking water during the water crisis.
How do I know if my borehole or rain water is safe to drink?
The only way that you can be certain whether water from alternative sources – whether it is rainwater or groundwater – is safe to drink is through a water sample test. Have a water sample tested in a registered laboratory, or use hydrogen-sulphide home tests to indicate whether the water has harmful bacteria that can cause vomiting or diarrhea.
How do I test my water?
The list of elements to check for is long (over 40) and each one has serious health implications. Use the South African National Standards tests or SANS 241. This is a trusted test used by municipalities or disaster-response teams every day to check our drinking water.
Is it sill safe to drink tap water as we draw water from the bottom of the dams?
Tap water remains a safe drinking water resource as long as it continues to comply with national water standard requirements. While the water at the bottom of dams is often of a poorer quality because of particles that concentrate and settle, it takes extra effort and care to abstract and treat this water – which remains the responsibility of the City of Cape Town.
What about bottled and spring water?
Typically bottled water is one of the safe sources to turn to. If you want to be assured that the bottled water has been tested, then look for the SANBWA label – the South African National Bottled Water Association.SANBWA tests and confirms that its members meet health standards. Another popular water source for many residents is spring water from iconic sites such as Newlands and Muizenberg springs. They are not part of the Cape Town water system and are thus not regularly tested by authorities. Interest groups may test the water from time to time and currently many people drink it without treatment. Ultimately, however, the regular drinking of this water without treatment is left to your own judgement and it is at your own risk.
Why shouldn’t I drink water straight out of my rainwater tank?
Although pure rain water is clean enough to drink, the water collected in rainwater tanks has been recovered from your roof and gutters which likely will have bird or rat droppings as well as leaves and dust which contains chemicals from air pollution. This water should be cleaned and disinfected before drinking.
What’s wrong with drinking untreated borehole or well point water?
Groundwater outside of Cities is often safe to drink, but it is wise to assume that all borehole and well point water in Cape Town should be treated before it would be suitable as drinking water. Cape groundwater are high iron and/ or high salt levels, as well as microbes from overflowing or leaking wastewater systems and from homemade pit latrines where a hole is dug in the ground.
What is the easiest way to make water safe to drink?
Boil your water for at least three minutes to ensure that water is free of microbes (bacteria, viruses and protozoa) to prevent diarrhoeal outbreaks. People with compromised immune systems, babies and the sick should use bottled or tap water.
Common household treatments include:
- Chlorine Dioxide
- Combination of Filtration and Disinfection
The World Health Organisation (WHO) provides many documents describing household treatment on their website. Drinking water quality guidelines can be found here and treatment of water following emergencies and disasters on these pages. The Centers for Disease Control and Prevention, or CDC, provides fact sheets on “Making Water Safe”.
What other methods are on offer?
There are many ways to treat water, and the performance among different methods varies extensively. Sometimes a combination of methods is advised for water sources with high risk of both microbial and chemical contamination (such as groundwater, river and wetland water). A set of common methods is shown here. For more information, see the table below.
How do I store my drinking water safely?
- Label drinkable water, collected and stored in clean (sterile) plastic/ glass/ stainless steel containers.
- You can use a baby bottle disinfectant (e.g. Milton) to sterilise your containers.
- Keep in a cool dark place to avoid any microbial or algal growth.
- It is also preferable to use food grade plastic which is determined by the number within the three-arrow triangle that classifies the type of plastic. Food grade means that no harmful BPA will leach into the water over time. The BPA-free plastics are those with numbers 1, 2, 4 and 5. Make sure that your clean water is sealed with a closed lid so that nothing can get in.
- Your hands also need to be clean when you handle it, as well as any scoop or funnel that you might use to get water out of your clean water storage container.
Day Zero prep – this week’s Bucket List:
- Ensure that you have enough CLEAN STORAGE CONTAINERS for drinkable water – and a dark, cool place to store them
- If you are likely to use an alternate source for drinking (rainwater or groundwater) make sure you have a sample of that water TESTED at a registered laboratory (SANS 241)- if you are going to share a neighbour’s borehole, you can offer to get the test done (sooner rather than later).
- Start thinking now about the TREATMENT METHOD that is best suited to you, your water sources and your needs and make sure you have what is needed.
For more information: